Author Topic: NiFe battery experience  (Read 2890 times)

mike90045

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NiFe battery experience
« on: December 10, 2018, 07:13:28 AM »
Starting a new thread for this. 

My NiFe thinking:
 Long rainy winters - tough to keep FLA batteries up and non-sulfated
 Cold temps, all batteries loose capacity, so over-size the bank
 NiFe are high internal resistance compared to FLA and so another oversize to allow for that.
 Wide voltage swing full to low, select charge controllers and inverter that can allow for that voltage


Original install 2011
https://www.facebook.com/media/set/?set=a.209715335768594&type=1&l=9747e4dde6

DIY battery lugs
https://www.facebook.com/media/set/?set=a.209740049099456&type=1&l=22ca4be983
  (still in great shape)


This last summer, while feeling fit and strong, I hired Fred (red shirt) to help with the labor of refreshing the cells electrolyte
https://www.facebook.com/media/set/?set=a.2113125788760863&type=1&l=1988b7f97a


and the prime mover (after the fusion plant 93 million miles away)
https://www.facebook.com/media/set/?set=a.224863967587064&type=1&l=cd69ef4dba


BruceM

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Re: NiFe battery experience
« Reply #1 on: December 10, 2018, 08:15:24 AM »
Here's some more good NIFE info Mike provided in an earlier post:
The lousy charge/discharge efficiency wasn't a surprise to me but the incredible 10-12 gallons a month water filling/consumption was.


> Maintenance
  lots, every 2 weeks, I add 5 or 6 gallons distilled, 20 gall was too much to do at a time, so I'd shifted the cycles around so I'm only doing a quarter of the bank at any 1 time.

> Charge/Use cycles
 ?? I charge and use them

> Efficiency
  about 60%, that's why they use so much water.

> DOD - how far down do you run them?
 the bank is 40,800 watt hours, (51v [42 cells] * 800Ah). My running voltage at sunrise is about 52v in summer, and 49v winter (longer nights) I figure my nightime consumption runs about 5Kwh. I sized to properly allow for their high internal resistance, and to supply starting surge for deep well pump, so I generally have low voltage droop.  I charge below recommended voltage, because that would fry my inverter.

ajaffa1

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Re: NiFe battery experience
« Reply #2 on: December 10, 2018, 08:18:12 AM »
Wow Mike, that`s a lot of batteries. just did a quick search and that set up would now cost around US$30,000 equivalent to 40,000 Australian dollars just for the cells. You use a Listeroid with an ST head as primary mover, what do you use to charge the cells? I`m assuming you charge with solar during the day and only use the generator for high usage or dull days. When this happens do you run direct off the generator or feed the battery bank from the generator and then draw everything through an inverter?

Your batteries were commissioned in 2011 and required the electrolyte replacing in 2017, I believe. Twice the life expectancy of standard lead acid batteries. Did the battery bank come back to full/original capacity after changing the electrolyte?

I am guessing you either live a long way from the grid or you really hate power companies, wish I had he money to follow suit.

Bob


ajaffa1

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Re: NiFe battery experience
« Reply #3 on: December 10, 2018, 10:22:37 PM »
Hey Glort, now you are a mind reader. I`ve been looking into doing exactly what you say. A neighbor of mine is now off grid using solar and fork lift batteries. The only thing he has problems with is pumping large volumes of water so he`s looking for a cheap diesel pump.

Bob

BruceM

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Re: NiFe battery experience
« Reply #4 on: December 11, 2018, 12:12:03 AM »
Pumping large volumes of water is just the sort of sunny day only activity that begs for lots of PV panels.  Franklin now makes PV direct centrifugal submersible well pump controllers for single and 3 phase of all sizes. The pump speed is varied based on PV power available.

I was tempted to revise my inverter controller to allow for variable speed well pump operation of my 1400 watt pump, but after Modafinil blew up and I went back to my old foggy MS brain function I decided I really didn't need it.  It could be a big plus on very large pumps.


mike90045

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Re: NiFe battery experience
« Reply #5 on: December 11, 2018, 02:01:11 AM »
Charging : either with the solar PV or the generator.  The generator  ( 6/1 & ST5 head ) feeds into the GEN input of the inverter  ( XW-6048 )  The inverter senses power and re-configures itself into a battery charger, so I crank the setting to 30A charging @ 62 V  and other loads run off the generator directly.  The Schneider XW series is really good at syncing to the listeroid and seamlessly switching load in or out. It also is programed to halt charging and assist the generator if the load exceeds programed generator limits.

Battery water, I buy from the water store, I use DI water, and it always has tested good, < 2ppm 
 I've bought a auto watering system, which has taken 3 months to arrive, because the caps are honking big, it requires adapters to convert the watering caps to fit the battery screw tops.  That's going to be a week long project to lace all the vinyl tubing and trim the pressure sensing tubes.
http://www.watermasterusa.net/how-we-do-it



mikenash

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Re: NiFe battery experience
« Reply #6 on: December 11, 2018, 03:41:13 AM »
When they say 3000 L/Hr or 5000 L/Hr or whatever - you need to look at the performance curve for the pump.  if you are pumping to, say, 50 metres elevation to run a little micro-hydro with the stored water - you might only get 10% of the performance or some such.  "Research the curve numbers" is key.  Cheers

BruceM

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Re: NiFe battery experience
« Reply #7 on: December 11, 2018, 07:12:49 AM »
Yes, Franklin is very proud of their PV direct inverters, and the price isn't cheap in the US either.  It made me feel good about my homebrew 5 step sine inverter development.

+1 MikeNash's comment on pumps. Any pump you buy should have a head vs flow rate performance chart so you know just what to expect.  If a pump is sold as 3 meters of head, and 12 LPM flow rate, the former means zero flow at that 3 meters, and the latter means 12 LPM at zero head or lift.  You will be very disappointed if you think that meant 12 LPM at 3 M. There should be no surprise if you understand the usual marketing approach used for pumps, and get the actual performance chart so you can find the flow rate at your intended head or pressure.  If they don't have a flow- head performance chart, pass on the pump.

The problem with automatic watering systems is that the batteries must be in an outside ventilated enclosure or you could have a Brown's gas explosion risk on your hands.  If you're in a cold winter climate, that doesn't work well with water filled tubing.

Any time you have high battery water use in lead acid batteries, you must be seriously overcharging. I have a hard time believing Mike's NIFE battery water use is also not caused by gross overcharging...either excessive current or voltage, but I must assume he has confirmed this as normal from other NIFE users.  I'd be monitoring gas bubbling, current and voltage throughout the charge cycle to try and figure out what's going on. If I had no other way of doing it, putting some cloth on the PV to reduce charging current would be useful to see if there's a level below which they will charge without gassing so darn much.  Clamp on DC amp meters are not that expensive now and most are adequate. 



mike90045

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Re: NiFe battery experience
« Reply #8 on: December 12, 2018, 01:17:51 AM »
Water usage.   I'm not over charging, I'm well under the suggested charge rate, and several volts under the suggested charge voltage (because I bought 2 spare batteries to be able to swap in, in case of a failure, but the maintenance required to keep a spare, was more than just wiring them up, but that bumped my string voltage up 3V, and thats above my inverter OVP shutdown).   In the summer, it takes about 3 days of good hard charging to get the capacity up enough that my charge amps start to taper off.   I've got a 800ah battery, charging at no more than 50A with both arrays full blast on a clear cold day.  NiFe is advertised at 75% efficient, but it's closer to 60% and the efficiency loss is in the electrolyzing water to gas.

BruceM

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Re: NiFe battery experience
« Reply #9 on: December 12, 2018, 06:49:53 AM »
A 50A charge rate is only 10 amps over the suggested minimum charge rate from Iron Edison!  Yikes.  They really are water hogs and there's nothing to be done about it but the automatic waterer. 

The summer charging scenaro you listed is 1200 AH or so into a lightly discharged battery, so it seems NIFE also has a big fall off in efficiency for the last 10% of charge. That's not a show stopper nor a big deal since sulfation is a non-issue for NIFE.

Very interesting, thanks, Mike.


mike90045

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Re: NiFe battery experience
« Reply #10 on: December 13, 2018, 05:44:16 AM »
    ..............Main consideration would be How do I get 1 Ton of batteries in there in one pack?  Maybe batteries go in front shed and everything else goes in the back and is just wired up ?  Will they deliver with a forklift?

And you need a doorway wide enough to forklift a battery pack thru.  Maybe a ramp so the forklift can get the batteries inside the door.  Maybe a overhead crane rail to roll the pack on in ?


ajaffa1

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Re: NiFe battery experience
« Reply #11 on: December 13, 2018, 06:09:08 AM »
Why not just buy a whole forklift and hook it up to the solar? That way you get the batteries you want a mobile machine to take them where you want them and a useful tool for the shed.

Bob

oldgoat

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Re: NiFe battery experience
« Reply #12 on: December 13, 2018, 01:07:06 PM »
Looking long term that would viable considering it costs $500 a year just to have the mains on tap. As it is at the moment it costs me nothing because of the credits I get from the feed in tariff.  It suits me to keep this arrangement going because my plasma cutter takes 7 Kva and the compressor for it is 3Kva which would be a shock for most inverters. After 2025 when the agreement runs out I will probably be too shaky to pick up a plasma and my family will tell me it is too dangerous for me to use an oxy torch.